1. Field of the Invention
The field of the invention is data processing, or, more specifically, methods and apparatus for workload balancing among power switching components in a multiphase switching power supply.
2. Description of Related Art
The development of the EDVAC computer system of 1948 is often cited as the beginning of the computer era. Since that time, computer systems have evolved into extremely complicated devices. Today's computers are much more sophisticated than early systems such as the EDVAC. Computer systems typically include a combination of hardware and software components, application programs, operating systems, processors, buses, memory, input/output devices, and so on. As advances in semiconductor processing and computer architecture push the performance of the computer higher and higher, more sophisticated computer software has evolved to take advantage of the higher performance of the hardware, resulting in computer systems today that are much more powerful than just a few years ago.
One area of technology that has experienced advances is the area of power supply technology—power supplies configured to provide power to components of personal computers, to servers, to computer peripherals, to server racks, and so on. Many power supplies are switching power supplies that have multiple phases to reduce heat generation and increase power delivery efficiency in power switching components of the power supply. In such power supplies each phase is typically associated with a particular set of power switching components. When the power supply is configured with a low load, operating with many phases may be inefficient due to switching losses present in the switching components of each phase. To reduce such inefficiencies some multiphase power supplies are configured to drop phases when operating under a low load. Current multiphase power supplies configured for dropping phases, however, typically drop or ‘turn off’ the same sets of power switching components in the same order when deactivating phases. That is, in normal operation of current power supplies, when a first phase is dropped, a specified set of components is deactivated, when a second phase is dropped, another specified set of components is deactivated, and so on. Moreover, the same order of deactivating sets of switching components is followed each time phases are dropped in the power supply. Some sets of power switching components of current multiphase power supplies are therefore active more often than other sets. As such, the power switching components of such active phases experience greater use, greater wear, and age at a different rate than those power switching components of phases that are not active as often.